The conversion of natural energy, e.g., solar energy, wind energy, ocean tide and wave energy, into electrical energy is well known. The use of such natural energy sources has become more desirable in recent years due to concerns over the effects of fossil fuels on the environment and also due to the increasing cost of fossil fuels. Further, it is widely recognized that fossil fuels are in limited supply, thus further emphasizing the need to turn to natural energy sources.
Although windmills are a well known means for exploiting wind energy, windmills suffer from several inherent disadvantages. Tall towers must typically be constructed to accommodate large-diameter rotors and to position them high enough in the airstream to avoid the undesirable effects of air turbulence caused by obstructions at ground level. Further, the major mechanical components, i.e., the generator and associated mechanical linkage to the turbine, as well as the turbine controls and positioning apparatus, are typically located atop the tower as well, thus making maintenance difficult and expensive. Further, windmills only effectively extract energy from a circular cross section of an airstream, thereby substantially limiting their capability of extracting power from the wind stream.
In an attempt to overcome the inherent limitations associated with windmills, the prior art has developed various different linear motion wind driven power plants wherein one or more carriages having sails attached thereto are moved about a closed-loop track by the wind. Such movement of the carriages effects the generation of electrical power via various different means.
Examples of such prior art linear motion wind driven power plants are provided in: U.S. Pat. No. 665,810 issued to Stretch; U.S. Pat. No. 1,923,971 issued to Evans; U.S. Pat. No. 3,730,643 issued to Davison; U.S. Pat. No. 4,114,046 issued to Yousef; U.S. Pat. No. 4,302,684 issued to Gogins; U.S. Pat. No. 4,589,344 issued to Davison; U.S. Pat. No. 5,134,305 issued to Senehi; British Patent No. 1,168,314 issued to Stenner; Russian Patent No. 977,849 issued to Shevchenko; and French Patent No. 76 02698.
Thus, although contemporary windmills have proven generally suitable for their intended purpose, they possess inherent deficiencies which detract from their utility and desirability in the marketplace. As such, it is beneficial to provide a means for harnessing the power of the wind and converting such power into electrical energy in a manner which is both efficient and comparatively simple to construct and operate.